Telephone system



Aug. 19 1924.

H. D. cuR lzR TELEPHONE SYSTEM Original Fi led men 20,

mvlamoa HIRAM n UR IE: BY

ATTORNEY Patented Aug. 19, 1924 isosnss UNITED STATES PATENT oFFicE.

HIRAM D. OURRIER, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCHBOARDAND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CO BEORATION OF ILLINOIS.

TELEPHONE SYSTEM.

Original application filed March 20, 1915, Serial No. 15,835.

Patent 1\To{1,4;39,07l. dated. December 19, 1922. Divided and thisapplication filed September 27, 1922.

Serial No. 590,760.

I '0 all whom it may concern:

Be it known that l, HIRAM D. Guanine, a citizen of the United States ofAmerica, residing at Chicago, county of Cook, and 5 State of Illinois,have invented certain new and useful Improvements in Telephone Sys tems,of which the following is a specification.

My invention relates to telephone systems in which link or cord circuitsare employed,

and has to do more particularly with socalled multiple line lamp systemsin which automatic ringing, meter service registairing means, secretservice, instantaneous disconnect and recall are provided, and has forits object a new and improved system of the above character.

An object of my invention is the pro vision of automatic meter servicemeans for registering the number of connections set up by the operatorbetween calling subscribers lines and called subscribers lines but whichmeter service means will not operate to register the establishedconnection should the called subscribers line be busy.

Another object of my invention is the provision of means for preventingthe application of ringing current to the called subscribers line,should the said called subscribers line by busy, even though the operator has operated the ringing key to apply ringing current to the saidcalled line, but should the said called line be idle when connection ismade therewith, and the ringing key is operated, ringing current will beconnected to said called line and at the same time the automatic servicemeans will operate to register the established connection between thecalling subscribers line and the idle called subscribers line.

The above-mentioned objects of my invention, as well as others will bemore particularly pointed out in the following speci fication andclaims.

The present application is a divisional application of my co-pendingapplication Serial No. 364,872, filed March 10, 1920, renewal of SerialNo.15,835, field March 20, 191-53, now Patent Number 1,439,071, grantedDecember 19, 1922.

For a better understanding of my inven tion, reference may be had to theaccom- Renewed March 10, 1920, Serial No. 364,872.

panying drawing in which is shown the common battery substations A and Btermihating in the central ofiice in line circuits multiple line lamps Sand multiple jacks J The right hand winding of the line relay LR is of acomparatively high resistance while the left hand winding is of acomparatively low resistance, the reasons for having these windings ofdifferent resistances will hereinai'ter appear. The line circuit asillus trated is known. as a multiple lamp line circuit in which thelamps S and jacks J appear before a number of operators so that any oneoperator may answer a call to the exclusion of the other operators. Thesubstation E and the line circuit L are simil ar in all respects to thesubstation A and line circuit L, except that the substation B is one ofa plurality of like substations which are connected to the lineconductors leading to the central oifice equipment.

The cord circuit C comprises the answering plug AP and calling plug CP,the two plugs being connected by the heavily marked conductors of thecord circuit and having the condensers K and K interposed. Associatedwith the answering end of the cord circuit is the answering sleevesupervisory relay AS and the answering tip supervisory relay AT forcontrolling the circuit of the answering supervisory lamp AL. I alsoprovide a test relay TR for controlling the circuit of the answeringsleeve supervisory relay AS, which relay controls the connection oftheoperators telephone set O to the strands of the cord circuit. The testrelay TR comprises a pair of windings, one a comparatively highresistance winding Sand the other a comparatively low resistance winding6. I also provide a link disconnect relay LD for making possible;instantaneous disconnect and recall, and a recall relay RR forsegregating a recall to the particular operator that previously answeredthe original call. Asso ciateol with the calling end of the cord circuitI provide a calling tip supervisory relay CT and a calling sleevesupervisory relay OS for controlling the circuit of the callingsupervisory lamp CL. The calling 'the strands'of the cord circuit.

sleeve supervisory relay SC also controls the disconnection of-theoperators set 0 from A party line ringing key BK is provided forconnecting one of a plurality of generators to the common ringing lead 2and for controlling the ringing control relay EC. The ringing controlrelay RC controls the ringing interrupter relay RI, which through themedium of the interrupter I applies ringing current from the common lead2 to the line of the called subscriber. Associated with the cord circuitC is a service registering device comprising a meter maget MM and ametercontrol relay MR.

Assuming that the subscriber at the substation A ishes to initiate acall, upon the removal of the receiver thereat, a circuit is closedthrough the line relay LR, the'line relay upon energizing closes acircuit through the multiple line lamps S. An operator upon noting theline lamp S glowing inserts the answering plug AP into the jack J of thecalling line. Upon the insertion of the answering plug AP into the jackJ, an energizing circuit is closed through cut-off relay CO and throughthe high resistance winding of the relay TR. This circuit extends frombattery through the high winding of said test relay, normal contact 3 ofthe link disconnect relay LD, through the sleeve contacts of the plug APand jack J and through the cut-oil relay CO to ground. 'The cutoff relayCO upon energizing disconnects thesubscri'bers line circuit from theline relay LR thereby causing the line lamps S to be eflaced. The testrelay TR, upon energizing, closes the tip strand of the cord circuit atits contact sand thereby closes an energizing ClICUllI through the.answering tip supervisory relay AT. The answering III tip supervisoryrelay AT, upon energizing,

prevents the premature glowing of the answering supervisory lamp AL- byopening its normal contact :5 and also prevents the closing of anenergizing circuit for link disconnect relay LD. A further result due tothe energizationof the test relay TB is the closing of a multiplecircuit, through its locking winding 6 and through the answering sleevesupervisory relay AS to the sleeve conductor of the answering plug AP.This circuit extends from battery through the windings of the answeringsleeve super visory relay AS and the locking winding of the test'relayTR to the contact '7 of the said test relay TR, then throughthenormalcontact 8 of the link disconnect relay LD. through the sleeve conductorof the answering plug AP and jack J, and through the cut-ofi' relay COto ground. This low resistan'c e: 'ath, extending to the sleeveconductor ot multiple jack J, prevents the test relay TB of another cordcircuit from'operatively energizing and connecting the operators set ofthe said second cord circuit to the line circuit of the callingsubscriber. Answering sleeve supervisory relay AS, upon energizing,connects the operators set 0 to the cord circuit through its alternatecontacts 9 and 10 and through the normal contacts 11 and 12 of thecalling sleeve supervisory relay CS The operator now being in connectionwith the calling subscriber inquires the wants of the said callingsubscriber. Assuming that it is the subscriber at the substation B thatis wanted, the operator tests the line of the called subscriber and ifit is idle she then inserts the calling plug G]? into the jack Jconnected to the line circuit of the called subscriber. If the line ofthe called subscriber is busy, the operator will receive the usual busyclick in her receiver notifying her of the condition of the called line,and will thereupon notify the calling subscriber that the called line isbusy. Upon the insertion of the calling plug Cl into the jack J anenergizing circuit is closed through the calling slccvc' supervisoryrelay CS and the cutoff relay C0 of the called line. This circuitextends from battery through the winding of the said calling sleevesupervisory relay CS. sleeve conductor of the calling plug CP and jackJ, and through the winding of the said cut-off CO to ground. The relayCO, upon energizing, disconnects the line relay LP. from the linecircuit of the called subscriber. The calling sleeve supervisory relay,upon energizing, disconnects the operators set O from the strands of thecord cirsuit at its contacts 11 and 12 and closes a circuit through thecalling supervisory lamp CL at its contact 13. The circuit for lamp CLextends from battery through the said calling lamp CL. end contact ll:oi ringing key RK, normal contact 16 of ringing control relay RC normalcontact 17 of the link disconnect relay LD, normal contact 18 of callingtip relay CT and through the alternate contact 13 of relay CS to ground.The callinglamp {illisthe customary supervisory lamp for indicating tothe operator when the called subscriber responds. The operator nextdepresses one of the ringing kcy plungers to connect one oi thegenerators to the common ringing lead 2, to initiate the operation 0-1?the automatic ringing equipment, and to close a circuit for the metercontrol relay MR. The circuit for the meter control relay MR, extendsfrom battery through the winding of said relay MR, alternate contact 14ct ringing key 12K normal contact 16 of ringing control relay RC, normalcontact 17 of link disconnect relay LD, normal contact 18 of the tipsupervisory relay CT and through the alternate contact 13 of the callingsleeve supervisory relay CS to ground. The meter relay Mlt. uponenergizing, closes a circuit through the magnet MIVI which then operatesto register a call upon the service meter, When the operator releasesthe pressure from the plunger of the ringing key RK, the end springs 14and 15 return to their normal position. The closing of the alternatecontact 15 of the end springs of the ringing key BK closes a circuitthrough the ringing control relay BC. This circuit extends from bat terythrough the winding of said relay RC, alternate contact of the endsprings 15, normal contact 18 of the calling tip supervisory relay CTand through the alternate contact 13 of the calling sleeve supervisoryrelay CS to ground. The ringing control relay RC, upon energizing,closes a locking circuit for itself at its alternate contact 16independent of the end spring 15, closes a circuit through theinterrupter relay RI and separates the talking strands of the callingend of the cord circuit from the strands of the answering end of thecord circuit. The said locking circuit for ringing control relay RCextends from battery through the winding of said relay, through itsalternate contact 16, through normal contact 17 of link disconnect relayLD, normal contact 18 of calling tip supervisory relay CT and throughalternate contact 13 of calling sleeve supervisory relay CS to ground.The circuit for the interrupter relay RI extends from battery throughthe interrupter I, through the winding of said relay RT, throughalternate contact 20 of the ringing control relay BC to ground. Theringing relay RI, upon energizing, connects ringing current from commonringing lead 2 to the line of the called subscriber.

Upon the response of the called subscriber. a circuit is closed throughthe calling tip supervisory relay CT, this circuit extends from batterythrough the lower winding of said relay CT, normal contact 21 ofinterrupter relay RI, ring contact of the calling plug CP and jack J,through the substation B, tip contacts of the jack J and plug CP, normalcontact 22 of ringing rclay RI, alternate contact 23 of relay CS, andthrough the upper winding of the calling tip supervisory relay CT toground. The relay CT, upon energizing, opens the locking circuit for theringing control relay PC and for the supervisory lamp CL at its contact18. The ringing control relay, upon de-energizing, opens the circuit ofthe ringing interrupter relay RI at its contact 26 and connects thestrands of the calling and called ends of the cord circuit, so thatconversation may now take place between the calling and calledsubscriber over the heavily marked conductors. The eftacement oi. thecalling lamp CL indicates to the operstar that the called party hasresponded.

Assuming now that the operator received a click in herear, when shetested the called line, due to its being busy, and that the era-tor didnot pay any attention to the click but inserted the calling plug Cl?into the ack J and then operated the ringing key BK, to connect ringingcurrent to the called subscribers line, ringing current will not beconnected to the called line in this instant, for the calling tip relayCT will energize, since an energizing circuit will be closed for itthrough the closed switchhook contacts of i the busy substation on thecalled line, to

open the energizing circuit of the ringing control relay RC at normalcontact 18 of said relay CT. The circuit of relay RC being open atnormal contact 18 of relay CT,

said relay RC will not energize when the ringing key Rh. is operated, toapply ringing current to the called line. The meter relay MR will notenergize to bring about the operation of the meter magnet MM due to itsenergizing circuit being opened at normal contact 18 of relay CT. Thusit will be obvious that no harm can be done by an operator plugging intoa jack leading to a busy line even though she attempts to apply ringingcurrent to the called line, nor will the connection be registered by theserv ice meter device.

Assuming now that converstation has been finished, the subscriber at thesubstation A,

upon replacing the receiver upon its switchhook, opens the energizingcircuit of the answering tip supervisory relay AT at the switchhookcontacts. The supervisory relay AT, upon de-energizing, closes anenergizing circuit for the link disconnect relay LD at its contact 5 andcloses a locking circuit for the test relay TR and for the sleevesupervisory relay AS at its contact 26. The locking circuit for thesleeve supervisory relay AS extends from battery through the Winding ofsaid relay, its alternate contact 27, normal contact 26 of relay AT,alternate contact 28 of relay AS and alternate contact 13 of relay CS toground. The locking cir' cuit for the test relay TR. extends frombattery through the winding of said relay, alternate contact 27 of relayAS, normal contact 26 of relay AT, alternate contact 28 of relay AS andalternate contact 13 of relay CS to ground. A further result due to thede-energization of the answering tip supervisory relay AT is the closingof a circuit through the answering supervisory lamp AL. This circuitextends from battery through the said lamp AL, normal contact 29 ofrelay RR, normal contact 5 of relay AT, alternate contact 28 of relay ASand alternate contact 13 of relay CS to ground. The circuit for the linkdisconnect relay LD extends from battery through the winding of saidrelay, normal contact 5 of relay AT, alternate contact 28 of relay ASand alternate contact 13 of relay CS to ground. The link disconnectrelay Ll), upon energizing,

- CT at the switchbook contacts.

disassociates the talking strands of the link circuit from the linecircuit, opens the circuit of the cut-oil relay CO at its normalcontactv 3 and connects the control relay CR to the sleeve of theanswering plug AP. he called subscriber B, upon replacing his receiverupon the receiver hook, opens the circuit of the calling tip supervisoryrelay The superisory relay CT, upon deenergization, closes a circuittorthe calling supervisory lamp CL. The circuit for the calling supervisorylamp extends from battery through the said lamp, alternate contact 17 oflink discon- 'neet relay LD, normal contact 18 of relay 'CTand alternatecontact 13 of relay CS to ground. The operator, upon noting the glowingof the answering supervisory lamp AL and the calling supervisory lampCL, removes the answering plug AP and the calling plug CP from theirrespective acks J and J. The removal of the calling plug C'P from thejack J allows the cut-oil relay CO and the calling sleeve supervisoryrelay CS to de-energize. The relay CS upon deenergizing, opens thelocking circuit for the link disconnect relay Ll), answering sleevesupervisory relay AS, test relay TR and for the supervisory lamps CL andAL. The relays, upon tie-energizing, permit the apparatus of the cordcircuit to return to normal as soon as the answering plug AP is removedfrom the jack J.

Should the calling subscriber wish to recall before the answering plugAP is removed from the jacket the line circuit L, he

may-{do so. The subscriber, upon removing h s -16C1V6l for a recall,closes a circuit through the recall relay RR extending from 'batterythrough the left-hand winding of the line relay LR, normal contact 30 ofcuton relay CC through the calling subscribers substation, tip contactof the jack J and plug AP, alternate contact 32 of relay LD through thelower winding of said recall relay RR and the normal contact 33 ofcontrol relay CR to ground. The subscriber upon removing his receiveralso closes a cir cuitthrough the high resistance winding of the linerelay 7 LR, this circuit extending from battery. through the lefthandwinding of the relay LR, normal contact 30 of the r cut-off relay CC,through the calling subscribers substation, normal contact 31 of relayCO and through the high resistance right-hand winding of the relay LR toground. The line relay 'LR does not energize at this time owing tothelow resistance pathextending through the recall relay RR and owing tothe special adjustment of contact 34 ofre-lay RR. The relay RR is soadjusted that upon the first slight movement of its armature its contactat is closed before its other contacts are moved. The relay-RR, uponenergizing, closes a lockconductor of the answering plug ing circuit foritself extending from battery through its upper winding, its alternatecontact 34:, normal contact 26 of relay AT, alternate contact 28 ofrelay AS and alternate contact 13 of l'Cl1l CS to ground. The relay RRalso closes an energizing circuit for the cut-oil relay CC ol therecalling subscribers line. This circuit extends from ground through thewinding of said cut-oll' relay, sleeve conductor of jack J and plug AP,alternate contact 3 of relay LD, alternate contact 36 of recall relay RRand through the resistance 35 to battery. The cutoff relay, uponenergizing, disconnects the line relay LR from the subscribefis linecircuit L before it has had time to energize and cause the line signalsS to be operated. A further result due to the ei'iergizing of the recallrelay RR is to flash the su iiervisory lamp AL. The flash circuit forthe supervisory lamp AL extends from battery through the said lamp AL,alternate contact 29 of the recall relay RR and through the interrupterI to ground. The operator, upon noting the flashing of the answeringsupervisory lamp AL, removes the calling plug CP' from the jack Jthereby allowing the calling sleeve supervisory relay CS to dc energize.The relay CS, upon de-energizing, opens the locking circuits foranswering sleeve supervisory relay AS, testing relay TR, recall relay RRand link disconnect rea-y LD. The link disconnect relay LD is madeslightly slow-acting to allow relays .AS, TR and RR to de-encrgize.before it deenergizes. The recall relay RR, upon de-en ergizing, opensthe circuit of the supervisory lamp AL at its alternate contact 29. Linkdisconnect relay Ll), upon de-energizing, immediately closes a circuitthrou h the high resistance winding of he test reT-ay TR at its normalcontact 3 before the cut-off rclay CO has had time to allow the linerelay LR to energize and cause the line signals S to glow. The testrelay TR, upon again energizing, closes a multiple circuit through itswinding 6 and through the answering sleeve supervisory relay AS to thesleeve AP in the same manner as hereinbetore described. The linkdisconnect relay LD upon deenergizing, also connects the talkingconductors of the answering plug AP to the strands of the link circuitC. The recall is then handled by the operator in the same manner aspreviously described for handling an original call.

Assuming now that the conversation has been terminated, that the callingsubscriber A and the called subscriber B have replaced their receivers,and that a second operator has received a call for the callingsubscriber A, the operator first tests the line of the subscriber A andfinding it idle inserts the calling plug of a cord circuit into a jack Jcon lllS nected to the line circuit of subscriber A. Upon inserting thecalling plug of the second operators link circuit into the jack J, anenergizing circuit is closed through the control relay GB of the cordcircuit C. This circuit extends from battery through the calling sleevesupervisory relay of the sec ond operators cord circuit, the sleeve 01":the calling plug, the sleeve of the jack J, sleeve of the answering plugAP of cord circuit C, alternate contact 3 of the link disconnect relayLD, normal contact 36 of recall relay and through the winding ofcontrol. relay CR to ground. The control relay OR energizes over thiscircuit and removes ground f om the lower winding of the recall relay RRso that when the second operator applies ringing current to the tipconductor of the calling plug GP, it will not cause the recall relay RRto be operated to cause the answering supervisory lamp AL to signal afalse recall.

Assuming now that a connection has been established, if an operatorshould attempt to listen in upon a busy line by inserting the answeringplug of an idle link circuit into a multiple jack of the busy line andthen touch the tip of another answering or call ing plug to the sleeveof the busy line in an attempt to energize the answering sleevesupervisory relay AS to connect the operators set 0 with the strands ofthe cord circuit that she has connected to the busy line, she will findthat she will be unable to energize the supervisory relay AS to connecther set 0, as ground is normally disconnected from the tip conductors ofboth the answering and calling plugs.

In working out my invention I have employed preferred circuitarrangements, all of which go to make an eflicient operating system, butit is to be understood thatl changes and modifications may be readilymade without departing from the spirit and scope of my invention.Therefore, I do not desire to be limited to the exact arrangement shownand described but aim to cover all such changes and modifications ascome within the spirit and scope of the appended claims.

Having described my invention, what I claim as new and desire to secureby Letters Patent, is:

1. A telephone system, including a plurality of telephone lines, linkcircuits for interconnecting said lines as calling and called lines,automatic ringing means and a connection register for said linkcircuits, operator-controlled means for actuating said ringing means toapply ringing current to the called line and for actuating said connection register when one of said link cir-. cuits is connected to anidle called line, and means to prevent the actuation of said ringingmeans and connection register by the operation of said 'key whenconnection is made with a busy called line.

2. In a telephone system, a plurality of telephone lines terminating injack terminals, link circuits for connecting to said jack terminals,automatic ringing means and a connection register for said linkcircuits, a key operable to actuate said ringing means to apply ringingcurrent to a called line and to actuate said connection register when alink circuit is connected to an idle called line, and means forpreventing the application of ringing current to the called line and theactuation of said connection register when connection of a link circuitis made with a busy'jack terminal.

3. In a telephone system, a subscriber s telephone line terminating inmultiple jack terminals, a link circuit for connecting to any one ofsaid terminals, service meter means for registering a connection betweensaid link circuit and one of said jack terminals, ringing means forapplying ringing current to said subscrihers line, a manually operatedkey for actuating said ringing means and service meter means when saidlink circuit is connected to an idle jack terminal, and means forpreventing the actuation of said ringing means and said service metermeans when connection is made with a busy ack terminal.

l. In a telephone system, a calling subscribers line and a calledsubscribers line, a link circuit for interconnecting said subscriberslines, ringing means for applying ringing current to said calledsubscribers line. service meter means for registering the connectionbetween said calling subscribers line and said called subscribers lineit said called line is idle, and means for preventing the operation ofsaid service meter means and said ringin means if said called line isbusy.

5. In a telephone system, a calling subscribers line and a calledsubscribers line, a link circuit for interconnecting said lines,automatic ringing means for applying ringing current to said calledline, connection register means for registering the number ofconnections between said subscribers lines, a key for controlling theactuation of said ringing means and said service meter means, and meansfor preventing the operation of both of said means when said called lineis busy and a connection is made therewith and said key operated.

6. A telephone system including a subscribers line, a link circuit forconnecting to said subscribers line, ringing means for applying ringingcurrent to said subscribers line, connection registering means forregistering the number of connections between said link circuit and saidlines, a key for actuating said ringing means and said registeringmeans, a relay controlled over said subscribers line, and

operable to disconnect ringing current from said. line when thesubscriber thereon responds, and also operable to prevent the actuationof said ringing means and said registering means when said key isoperated it the said called subscribers line is busy When connection ismade therewith.

7. In a telephone system including telephone lines, link circuits forinterconnecting saidlines, automatic ringing means for applying ringingcurrent to said lines as called lines, service meter means forregistering the number of connections between said lines and said linkcircuit, a key adapted' to be operated to actuate said service metermeans and ringing mean when a link circuit is connected to an idle lineand electromagnetic means for preventing the actuation of said servicemeter means and said ringing means when connection is made with a busyline.

8. In a telephone system, including a calling subscribers line and acalled subscribers line, a link circuit for interconnecting saidsubscribers lines in conversational circuit,

7 connection registering means operable to register a connection betweensaid link circu'it and said called line, ringing means operable to applyringing current to said called line, manually operated means foretfecting the operation of said registering means and said ringing meanswhen said link circuit is connected to said called l ne and said calledline is idle, and electromagnetic means for preventing the open ation ofsaid registering means and ringing means it said called line is busy.

9. In a telephone system including telephone lines, link circuits forinterconnecting said lines, means "for registering thr number ofconnections between said link circuit and said lines, when said linesconnected to are idle, ringing means for said link cir cuits forapplying ringing current to said connected to idle lines, andelectromagnetic means for preventing the registration of a connectionand the application of ringing current when a connecti n is made with abusy line.

10. In a telephone system the combination with a plurality oi telephonelines, a linl; circuit for interconnecting a calling one with a calledone of the said lines, a connez'tion register for the said link circuit,a ringing F5 key adapted when operated to continumistr apply a source ofintermittent ringing current to the terminals oi the called line towhich the link circuit has been connected. means to cause the actuationof said reg- .isterwhen the said ringing current has been applied to thecalled. line terminals, and means to prevent the actuation of: the saidregister and. the said ringing means by the operation'ot the said key,when connection is made with a terminal of a busy desired line.

Signed by me at Chicago, in the county ot Cook and State of Illinois,this 25th day of $epte1nber, 1922.

l-lIRAM D. CURRIER.

